/*
 *  Copyright:  (C) 2018 LingYun IoT System Studio
 *              All rights reserved.
 *
 *  File name:  socket_server_thread.c
 *Description:  Use multithreading to complete the programming of the socket server.
 *
 *    Version:  1.1
 *     Author:  Guo Wenxue <guowenxue@gmail.com>
 *		        Copied by Zhu Tianyin <zhuty_cn@163.com>
 *  ChangeLog:  1.0  Release initial version in 2018.
 *              1.1  Copy and change some details on "02/02/2021"
 */

#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <getopt.h>
#include <pthread.h>
#include <ctype.h>

typedef void *(THREAD_BODY) (void *thread_arg);

void *thread_worker(void *ctx);
int thread_start(pthread_t *thread_id, THREAD_BODY *thread_workbody, void *thread_arg);

void print_usage(char *progname)
{
    printf("%s usage: \n", progname);
    printf("-p(--port): specify server listen port.\n");
    printf("-h(--Help): print this help information.\n");

    return ;
}

int main(int argc, char **argv)
{
    int             sockfd = -1;
    int             rv = -1;
    struct sockaddr_in servaddr;
    struct sockaddr_in cliaddr;
    socklen_t       len;
    int             port = 0;
    int             clifd;
    int             ch;
    int             on = 1;
    pthread_t       tid;

    struct option opts[] = {
        {"port", required_argument, NULL, 'p'},
        {"help", no_argument, NULL, 'h'},
        {NULL, 0, NULL, 0}
    };

    while( (ch=getopt_long(argc, argv, "p:h", opts, NULL)) != -1 ) 
	{
		switch(ch)
		{
			case 'p':
				port=atoi(optarg);
				break;

			case 'h':
				print_usage(argv[0]);
				return 0;
		}

	}

	if( !port )
	{
		print_usage(argv[0]);
		return 0;
	}

	sockfd=socket(AF_INET, SOCK_STREAM, 0);
	if(sockfd < 0)
	{
		printf("Create socket failure: %s\n", strerror(errno));
		return -1;
	}
	printf("Create socket[%d] successfully!\n", sockfd);

	setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));

	memset(&servaddr, 0, sizeof(servaddr));
	servaddr.sin_family=AF_INET;
	servaddr.sin_port = htons(port);
	servaddr.sin_addr.s_addr = htonl(INADDR_ANY); /* listen all the IP address on this host */
	//inet_aton("192.168.0.16", &servaddr.sin_addr); /* Only listen specify IP address on this host */

	rv=bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
	if(rv < 0)
	{
		printf("Socket[%d] bind on port[%d] failure: %s\n", sockfd, port, strerror(errno));
		return -2;
	}

	listen(sockfd, 13);
	printf("Start to listen on port [%d]\n", port);

	while(1)
	{ 
		printf("Start accept new client incoming...\n");

		clifd=accept(sockfd, (struct sockaddr *)&cliaddr, &len);
		if(clifd < 0)
		{
			printf("Accept new client failure: %s\n", strerror(errno));
			continue;
		}

		printf("Accept new client[%s:%d] successfully\n", inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));

        /*The value of clifd is passed in, not the address of clifd*/
		thread_start(&tid, thread_worker, (void *)clifd);
	}


	close(sockfd);

	return 0;
}

int thread_start(pthread_t * thread_id, THREAD_BODY * thread_workbody, void *thread_arg)
{
	int                 rv = -1;
	pthread_attr_t      thread_attr; 

	if( pthread_attr_init(&thread_attr) )
       	{
	       	printf("pthread_attr_init() failure: %s\n", strerror(errno));
		goto CleanUp;
       	} 
	
	if( pthread_attr_setstacksize(&thread_attr, 120*1024) )
       	{
	       	printf("pthread_attr_setstacksize() failure: %s\n", strerror(errno));
		goto CleanUp;
	} 
	
	if( pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED) )
       	{
	       	printf("pthread_attr_setdetachstate() failure: %s\n", strerror(errno));
		goto CleanUp;
       	} 
	
	/* Create the thread */
       	if( pthread_create(thread_id, &thread_attr, thread_workbody, thread_arg) )
	{
		printf("Create thread failure: %s\n", strerror(errno));
	       	goto CleanUp;
	}

	rv = 0;
						    
CleanUp:
       
	/* Destroy the  attributes  of  thread */ 
	pthread_attr_destroy(&thread_attr); 
	return rv;
}

void *thread_worker(void *ctx)
{
	int                  clifd;
	int                  rv;
       	char                 buf[1024]; 
	int                  i;

	if( !ctx )
	{
		printf("Invalid input arguments in %s()\n", __FUNCTION__);
		pthread_exit(NULL);
	}

	clifd = (int)ctx;
	
	printf("Child thread start to communicate with socket client...\n");
	
	while(1)
	{ 
		memset(buf, 0, sizeof(buf));
	       	rv=read(clifd, buf, sizeof(buf));
	       	if( rv < 0)
	       	{
		       	printf("Read data from client sockfd[%d] failure: %s and thread will exit\n", clifd, strerror(errno));
		       	close(clifd);
		       	pthread_exit(NULL);
	       	}
		else if( rv == 0)
	       	{ 
			printf("Socket[%d] get disconnected and thread will exit.\n", clifd);
		       	close(clifd);
		       	pthread_exit(NULL);
	       	} 
		else if( rv > 0 ) 
		{
		       	printf("Read %d bytes data from Server: %s\n", rv, buf);
	       	}

		/* convert letter from lowercase to uppercase */
		for(i=0; i<rv; i++)
		{
			buf[i]=toupper(buf[i]);
		}
	       
		rv=write(clifd, buf, rv);
	       	if(rv < 0)
	       	{
		       	printf("Write to client by sockfd[%d] failure: %s and thread will exit\n", clifd, strerror(errno));
		       	close(clifd);
		       	pthread_exit(NULL);
	       	}
	}
}

